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    <title>Spring Boot 条件化配置深度解析</title>
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    <!-- Hero Section -->
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            <div class="max-w-4xl mx-auto text-center">
                <h1 class="text-5xl md:text-6xl font-bold mb-6 leading-tight">
                    Spring Boot 条件化配置
                    <span class="block text-3xl md:text-4xl mt-4 font-light opacity-90">深度解析与实践指南</span>
                </h1>
                <p class="text-xl md:text-2xl opacity-90 leading-relaxed">
                    探索 Spring Boot 自动化配置的核心机制，掌握条件化注解的精髓
                </p>
                <div class="mt-8 flex justify-center space-x-4">
                    <span class="inline-flex items-center px-4 py-2 bg-white bg-opacity-20 rounded-full">
                        <i class="fas fa-code mr-2"></i> 源码分析
                    </span>
                    <span class="inline-flex items-center px-4 py-2 bg-white bg-opacity-20 rounded-full">
                        <i class="fas fa-cogs mr-2"></i> 实战应用
                    </span>
                    <span class="inline-flex items-center px-4 py-2 bg-white bg-opacity-20 rounded-full">
                        <i class="fas fa-lightbulb mr-2"></i> 最佳实践
                    </span>
                </div>
            </div>
        </div>
    </section>

    <!-- Main Content -->
    <main class="container mx-auto px-6 py-12 max-w-6xl">
        <!-- Introduction -->
        <section class="bg-white rounded-2xl shadow-xl p-8 md:p-12 mb-12 card-hover">
            <p class="text-lg leading-relaxed text-gray-700">
                <span class="drop-cap">在</span>Spring Boot 中，自动化配置是一项关键功能，它能够根据应用的上下文动态地选择和启用不同的配置。Spring Boot 提供了丰富的条件化配置机制，这使得开发者能够通过一些条件来灵活地启用或禁用某些配置。条件化配置的实现主要通过注解的方式来完成，Spring Boot 使用 <code class="highlight-box">@Conditional</code> 注解及其相关的注解（如 <code class="highlight-box">@ConditionalOnClass</code>、<code class="highlight-box">@ConditionalOnMissingBean</code> 等）来控制配置的加载。
            </p>
        </section>

        <!-- Concept Map -->
        <section class="bg-white rounded-2xl shadow-xl p-8 md:p-12 mb-12">
            <h2 class="text-3xl font-bold mb-8 text-center text-gray-800">
                <i class="fas fa-sitemap mr-3 text-purple-600"></i>条件化配置体系结构
            </h2>
            <div class="mermaid">
                graph TD
                    A[Spring Boot 条件化配置] --> B[@Conditional 核心注解]
                    A --> C[Condition 接口]
                    A --> D[常用条件注解]
                    A --> E[自动配置机制]
                    
                    B --> B1[组合注解]
                    B --> B2[条件判断]
                    
                    C --> C1[matches 方法]
                    C --> C2[ConditionContext]
                    C --> C3[AnnotatedTypeMetadata]
                    
                    D --> D1[@ConditionalOnClass]
                    D --> D2[@ConditionalOnMissingBean]
                    D --> D3[@ConditionalOnProperty]
                    D --> D4[@ConditionalOnWebApplication]
                    
                    E --> E1[@EnableAutoConfiguration]
                    E --> E2[AutoConfigurationImportSelector]
                    E --> E3[spring.factories]
                    
                    style A fill:#667eea,stroke:#fff,stroke-width:3px,color:#fff
                    style B fill:#764ba2,stroke:#fff,stroke-width:2px,color:#fff
                    style C fill:#764ba2,stroke:#fff,stroke-width:2px,color:#fff
                    style D fill:#764ba2,stroke:#fff,stroke-width:2px,color:#fff
                    style E fill:#764ba2,stroke:#fff,stroke-width:2px,color:#fff
            </div>
        </section>

        <!-- Section 1: @Conditional 注解 -->
        <section class="bg-white rounded-2xl shadow-xl p-8 md:p-12 mb-12">
            <h2 class="section-title text-3xl font-bold mb-8 text-gray-800">
                1. @Conditional 注解及其实现机制
            </h2>
            
            <p class="text-lg leading-relaxed text-gray-700 mb-8">
                <code class="highlight-box">@Conditional</code> 是 Spring Framework 提供的一个核心注解，用于根据一定条件判断是否创建某个 Bean。<code class="highlight-box">@Conditional</code> 注解是一个组合注解，它可以与其他多个条件化注解一起使用，控制某个 Bean 是否生效。
            </p>

            <div class="bg-gray-50 rounded-xl p-6 mb-8">
                <h3 class="text-xl font-semibold mb-4 text-gray-800">
                    <i class="fas fa-code mr-2 text-purple-600"></i>@Conditional 注解的定义
                </h3>
                <pre class="code-block p-4"><code>@Target({ElementType.TYPE, ElementType.METHOD})
@Retention(RetentionPolicy.RUNTIME)
@Import(ConditionalConfiguration.class)
public @interface Conditional {
    Class&lt;? extends Condition&gt;[] value();
}</code></pre>
            </div>

            <div class="bg-purple-50 rounded-xl p-6">
                <p class="text-gray-700 leading-relaxed">
                    <i class="fas fa-info-circle mr-2 text-purple-600"></i>
                    <code class="highlight-box">@Conditional</code> 注解的 <code class="font-mono bg-purple-200 px-2 py-1 rounded">value</code> 属性接收一个实现了 <code class="font-mono bg-purple-200 px-2 py-1 rounded">Condition</code> 接口的类。这些 <code class="font-mono bg-purple-200 px-2 py-1 rounded">Condition</code> 类定义了条件判断的逻辑。只有当 <code class="font-mono bg-purple-200 px-2 py-1 rounded">Condition</code> 判断为 <code class="font-mono bg-purple-200 px-2 py-1 rounded">true</code> 时，Bean 才会被创建和注册到应用上下文中。
                </p>
            </div>
        </section>

        <!-- Section 2: Condition 接口 -->
        <section class="bg-white rounded-2xl shadow-xl p-8 md:p-12 mb-12">
            <h2 class="section-title text-3xl font-bold mb-8 text-gray-800">
                2. Condition 接口与条件判断
            </h2>
            
            <p class="text-lg leading-relaxed text-gray-700 mb-8">
                <code class="highlight-box">Condition</code> 接口定义了一个方法 <code class="font-mono bg-purple-200 px-2 py-1 rounded">matches</code>，该方法用于判断某个条件是否满足。如果 <code class="font-mono bg-purple-200 px-2 py-1 rounded">matches</code> 方法返回 <code class="font-mono bg-purple-200 px-2 py-1 rounded">true</code>，则 Spring 会注册相关的配置 Bean。
            </p>

            <div class="grid md:grid-cols-2 gap-6 mb-8">
                <div class="bg-gray-50 rounded-xl p-6">
                    <h3 class="text-xl font-semibold mb-4 text-gray-800">
                        <i class="fas fa-file-code mr-2 text-purple-600"></i>Condition 接口定义
                    </h3>
                    <pre class="code-block p-4 text-sm"><code>public interface Condition {
    boolean matches(ConditionContext context, 
                   AnnotatedTypeMetadata metadata);
}</code></pre>
                </div>
                
                <div class="bg-purple-50 rounded-xl p-6">
                    <h3 class="text-xl font-semibold mb-4 text-gray-800">
                        <i class="fas fa-list-ul mr-2 text-purple-600"></i>核心参数说明
                    </h3>
                    <ul class="space-y-3">
                        <li class="flex items-start">
                            <i class="fas fa-chevron-right mr-2 text-purple-600 mt-1"></i>
                            <div>
                                <code class="font-mono bg-purple-200 px-2 py-1 rounded">ConditionContext</code> 提供了条件判断的上下文信息，主要包括 <code class="font-mono bg-purple-200 px-2 py-1 rounded">Environment</code> 和 <code class="font-mono bg-purple-200 px-2 py-1 rounded">BeanDefinitionRegistry</code> 等。
                            </div>
                        </li>
                        <li class="flex items-start">
                            <i class="fas fa-chevron-right mr-2 text-purple-600 mt-1"></i>
                            <div>
                                <code class="font-mono bg-purple-200 px-2 py-1 rounded">AnnotatedTypeMetadata</code> 提供了注解的元数据，开发者可以通过它来获取注解的相关信息。
                            </div>
                        </li>
                    </ul>
                </div>
            </div>

            <div class="bg-gray-50 rounded-xl p-6">
                <h3 class="text-xl font-semibold mb-4 text-gray-800">
                    <i class="fas fa-flask mr-2 text-purple-600"></i>OnClassCondition 源码分析
                </h3>
                <pre class="code-block p-4 text-sm"><code>public class OnClassCondition implements Condition {
    @Override
    public boolean matches(ConditionContext context, AnnotatedTypeMetadata metadata) {
        String[] classNames = (String[]) metadata
            .getAnnotationAttributes(ConditionalOnClass.class.getName())
            .get("value");
        
        if (classNames == null) {
            return false;
        }

        ClassLoader classLoader = context.getClassLoader();
        for (String className : classNames) {
            try {
                Class.forName(className, false, classLoader);
            } catch (ClassNotFoundException ex) {
                return false;
            }
        }
        return true;
    }
}</code></pre>
            </div>
        </section>

        <!-- Section 3: 常见条件化注解 -->
        <section class="bg-white rounded-2xl shadow-xl p-8 md:p-12 mb-12">
            <h2 class="section-title text-3xl font-bold mb-8 text-gray-800">
                3. 常见条件化注解
            </h2>
            
            <p class="